Commit Message

The current implementation of os_host_main_loop_wait() on Windows,
returns 1 only when a g_poll() event occurs because the return value of
select() is overridden. This is wrong as we may skip a socket event, as
shown in this example:
1. select() returns 0
2. g_poll() returns 1 (socket event occurs)
3. os_host_main_loop_wait() returns 1
4. qemu_iohandler_poll() sees no socket event because select() has
return before the event occurs
5. select() returns 1
6. g_poll() returns 0 (g_poll overrides select's return value)
7. os_host_main_loop_wait() returns 0
8. qemu_iohandler_poll() doesn't check for socket events because the
return value of os_host_main_loop_wait() is zero.
9. goto 5
This patch use one variable for each of these return values, so we don't
miss a select() event anymore.
Also move the call to select() after g_poll(), this will improve latency
as we don't have to go through two os_host_main_loop_wait() calls to
detect a socket event.
Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
---
main-loop.c | 27 +++++++++++++--------------
1 file changed, 13 insertions(+), 14 deletions(-)